Lighting 101: Strobe/Ambient Balance — A Shorthand Way of Thinking

Okay, so by now you should have a decent understanding of how you can balance flash flash with ambient light. In this segment, we'll give that process a little shorthand language to help you understand other photographers when they talk about the way the lit a photo.

Here, I want to accomplish two things:

1. To set you up with a way of quickly understanding and/or communicating how a given photo was balanced, and

2. To not have to repeat full, detailed number-by-number walk-throughs on this process every time we mix flash and ambient. Which is just about every lit photo we shoot.

First, a little confession. Lots of times when I am explaining to someone how a photo was lit, they will want to know everything -- shutter speed, ISO, aperture, flash power settings, etc.

I have to be honest with you -- most of the time I have no idea what those numbers were. It is not that I forgot them. It's just that I didn't care enough about them when I was making the photo to remember them, so they never registered.

No kidding, if you ask a professional PJ, "What's your favorite F/stop?" He or she will know you are talking about the amateurs that sidle up to us at a football game. We are really not that numbers oriented.

Truth be told, I don't think in terms of absolute F/stops and shutter speeds. They are not what is important. It's the relationship between the different light levels that is important.

Take the photo of my friend Shadi, above. It was shot on a hazy, colorless afternoon in Dubai. Here was the process to make this photo:

1. Find the exposure for the ambient. (That's easy - just grab a shot on auto or zero out a manual exposure.)

2. On manual mode, set the camera to underexpose the scene by two stops.

3. Set the camera to tungsten WB, to shift everything from dark grey to dark blue.

4. Light Shadi from the front with a flash with a CTO gel (plus an additional 1/4 CTO gel for extra warmth.)

5. Rim light him (from behind, low) with two ungelled flashes, at about two stops down compared to the main flash. That is the actual relative exposure level hitting Shadi, already accounting for the fact that that the flashes were ungelled. (The gel eats light from the key flash. So the rims might have actually been set 3 to 3 1/2 stops down in terms of absolute power settings.)

If I were talking to another pro about this photo, I would likely just say this:

"We dropped the ambient two stops, shot on tungsten, CTO'd the key light (plus an extra quarter cut) and left the rim lights ungelled, about two stops below the main."

That sentence tells me everything I need to know, because it starts with an assumed reference: They properly exposed key light.

What were the exposure settings? Can't remember, and don't care. It's just not that important.

What is important is the relationship between the flash exposure and the ambient exposure: About two stops. And, just to make things more complex, the fact that we did the tungsten-ambient shift, overgelled the key and left the rims straight.

Understanding this shorthand way of thinking drills into your head that it is the relationships between the lights that matter -- not the absolute settings.

There are two power ratios to think about here: The relationship between the key light and the ambient, and the relationship between the key light and the fill (and/or background) flashes.

Given that our first example was a little complex, lets walk through some familiar photos, thinking and talking in shorthand about the balance.

"Sodium vapor ambient. Shot on daylight, underexposed the wind tunnel by 1 2/3 stops, bare flash behind the fan blades about a stop hot."

So, this tells us that the reference point for the exposure was actually between the exposures for the flash and the ambient. This photo is underexposed by 1 2/3 stops for the ambient, and the flashed area is one stop overexposed.

My ambient is 1 2/3 stops down -- on the wrong color balance -- and my flash is a stop overexposed. This photo should really suck, right?

Honestly, if one area of the frame were "correctly" exposed, it would not be as interesting. The important thing is that I chose these relative brightness levels, without being chained to my camera's ambient meter or the "proper value" of some incident flash meter.

(You can read more about this photo, including those unimportant f/stops and shutter speeds, here.)

Let's try it again:

"Shot on daylight setting in a tungsten room. Exposed for the flash under the orange bowl on Chris' face and dropped the room by a stop and a half."

What's my reference point? The flash's exposure on Chris's face. I put the flash under the bowl on low power, shot a couple of frames until I got the aperture right. (Easier than adjusting that flash.) And then dialed in the shutter to set the ambient to a stop-and-a-half down.

Technically, I supposed I should have shot in tungsten, but why get rid of all of that surreal color? Besides, have you seen Chris Hurtt's natural skin tone at midnight in a bar in a Dubai hotel?

I'm just sayin'.

Thinking about your flash and ambient in terms of their relative (as opposed to absolute) values not only makes you quicker at reverse engineering photos, but makes you quicker at pre-visualizing and creating them, too.

Sometimes you are working so far above the ambient that it is not a component of the exposure at all. Yes, you need to communicate that. But given that you are far enough above the ambient for it not to be an issue it really doesn't matter if you are five stops over, or twelve:

"We killed the ambient; umbrella at camera left, gobo'd to control the reflection on the locker; ring light fill about two stops down."

What was the ISO? The f/stop? The shutter speed? The flash's power settings?

Don't remember, don't care. Because all you need to know to reproduce that look is in the short description above. And if you start thinking about your photos this way, you'll find that the lighting design comes easier and easier.

(More on this assignment here.)

Okay, one more:

"Exposed for flashes in chopper -- one in front cabin, two in back -- and dropped the ambient by three stops."

That is all there is to it, and tells you everything you need to know about lighting and exposing photo.

Again, the absolute settings do not really matter, from a reverse-engineering point of view. They are yours to choose based on what depth of field (or rotor-stopping shutter speed) you want.

(More on this assignment here.)

So, does this stuff make sense? It had better, because you are going to be seeing a lot more of this lingo in the future around here.

Don't worry, it is not like the posts are going to be three sentences long from here on out. (You wish...) There is still a lot of stuff to think about when you are creating and lighting a photo. It's just that we do not really need to re-invent that wheel any more.

Instead, I'll just give you the info in a way that helps you to think on your feet better and link to this page for the newbs.

I realize that the vast majority of the people who read this site are amateurs. But as many times as we'll be going through this process, we should start talking and thinking like pros. And if you just dropped in and this is all Greek to you, definitely give the Balancing Flash and Ambient posts another read...

Next: Reverse Engineering Other Shooters' Light


Brand new to Strobist? Start here | Or jump right to Lighting 101
Connect w/Strobist readers via: Words | Photos

Comments are closed. Question? Hit me on Twitter: @Strobist


Blogger Aaron E said...

This was just the post I needed to read. Drilling this way of thinking into my head is so much easier...and more fun...than always being consumed so much with the numbers. This is now a tab so that when ever I want to ask for the numbers (breaking a bad habit) I will re-read this.
Thanks David. You rock.

October 01, 2008 12:35 AM  
Blogger Michael G. Manoukian said...

Good for you!!! I'm happy you are making the switch in your posts. Even of most of your readers are amateur, they are your readers ergo know or are learning all about lighting relationships. I appreciate the respect you show by not "dumbing" it down for the majority who understand.

Look forward to plenty more posts with pro descriptions.

Mike M.

October 01, 2008 12:40 AM  
Anonymous Brandon D. said...

I love the attitude of breaking "The Rules" in order to enhance creativity.

October 01, 2008 12:49 AM  
Blogger Jason said...

As usual great post :) I need to start thinking more in these terms than in absolute values.

October 01, 2008 1:21 AM  
Blogger Jason said...

great post! Thinking in these terms would make it a whole lot easier to produce results like you said.

October 01, 2008 1:23 AM  
Anonymous Eddy said...

I'm sure this is not Greek.
Believe me, i'm from Greece :)

October 01, 2008 2:13 AM  
Anonymous Ryan Scott said...

That's good news, David. the site is fantastic for people just starting out with the whole light balancing idea, but the site is layed out well enough that you can easily navigate and read/learn the basics on your own. I appreciate that the site is growing in the direction of those that "get it" and have for a bit now. When I have to reread how to balance flash to ambient over and over again it can get, well, boring. Kudos for recognizing that.

October 01, 2008 2:26 AM  
Anonymous Jamie M. said...

Now I don't feel like a loser for having to look at my EXIF info to tell people that stuff. People make things way too complicated.


October 01, 2008 2:57 AM  
Anonymous Mike C said...

I'm glad to see that this is the way that things are going on your blog. It's been the older posts of yours where I have realized that it is this relationship between your lights that is important and not the actual values, and I think it has helped in my photography - and it's nice to see that is how you're explaining it now here.

October 01, 2008 3:12 AM  
Blogger Larry LaCom said...

DH, Your teaching is so good, that I'm pretty sure I got all what you said here before you said it. Not that I'm that smart (or my photos that good), but like you're pointing out, this is the "shorthand" way of understanding light, and I've practiced Strobist techniques enough to think this way for some time. Thank you for validating the way my mind has been working on these lighting techniques.

October 01, 2008 3:19 AM  
Anonymous Brett said...

That makes me feel much better about not remembering any of the settings for a shot. What power was the stobe on? No idea. I only remember a setting if it was really interesting (and even then I normally need to check in the EXIF data to confirm it).

Having said that I do use a script to add some EXIF data back into each image before posting (just in case someone else cares)

October 01, 2008 3:26 AM  
Anonymous Mike said...

Superb! I like this approach. The shorthand is quite clarifying.

October 01, 2008 3:48 AM  
Blogger ShotsbyRick said...

Ah ha! Nicely done. I never remember my setting's either, always have to refer to the exif data from the photo to get it. Of course, then I think "whoa! How did that happen!" Thanks for bringing it up a knotch David.

October 01, 2008 3:59 AM  
Anonymous Matt Kirwan said...


you say the majority of strobists are amateurs, I disagree! - When I discovered strobist I was blown away by the quality of the photography coming through the flickr pool. a professional photographer it truly was a humbling experience to be viewing pictures of these 'amateurs'.

I don't think shortening the explanation will cause too much hassle - it already looks like you have converted many people to designing light as opposed to geeking over light meters.

Keep up the good work!

Matt Kirwan

October 01, 2008 4:05 AM  
Anonymous Russell (Australia) said...

Hi David,
been reading your blog for about 6 months, what a great resource! inspired me to get back into photography --
I actually find this shorthand approach easier to understand than the longwinded versions haha.
Look forward to reading future posts and learning even more!

Russell (Australia)

October 01, 2008 4:30 AM  
Anonymous strongbif said...

You just rock my world.

October 01, 2008 4:42 AM  
Anonymous Anonymous said...

Maybe in the future could you show each light by itself and their appropriate contribution? Especially on the ones using another speed light as fill with no ambient contributions.

October 01, 2008 5:49 AM  
Blogger Dario D. said...

I think this mentality nails the problem of many photographers right on the head.

It probably goes hand-in-hand with the scanning-electron-microscope users who analyze lens sharpness and other such things down to the pixel, and are essentially just too preoccupied with the details to focus on the heart of the matter: the shot, and how to get it.

October 01, 2008 6:31 AM  
Blogger Matt Hunt said...

Good post David.

IMHO there is too much interest in numbers throughout photography and this post illustrates the point that being able to quote numbers does not mean that one understands what those numbers represent in terms of the picture presented.

Following your advice to reverse-engineer images has proved very useful in losing the interest in numbers. Instead it becomes a mental discussion (between my 4 brain cells it can get really intense) about what is ambient, what is strobe, where and covered with what and why.

Thinking this way makes the process of taking the picture faster too, leaving more time for creation?

October 01, 2008 6:34 AM  
Blogger Adam said...

Two things that made me happy about this particular post.

1) When I first visited this site about 18 months ago I would have been baffled by the short hand descriptions. However it's clear as day how far I've moved on with my understanding of controlled lighting because you'd apparently now speak to me as a "pro" :)

2) I made strobist front page again! Where you say? I'm about 20px wide on the full res shot of Chris Hurtt just to the top right of the glowing orb.


October 01, 2008 6:41 AM  
Anonymous Anonymous said...

"We dropped the ambient two stops, shot on tungsten, CTO'd the key light (plus an extra quarter cut) and left the rim lights ungelled, about two stops below the main."

You're starting to sound like Joe McNally. Not sure whether that's a good thing or not...

October 01, 2008 7:01 AM  
Anonymous Stefan Tell said...

This is the best explanation or how-to I have read on how to think when using off-camera flash yet. Easy to understand, and even better, easy to know know where to start your thinking.

Not that the rest of this site is bad (I've been reading it a lot), but this was spot on and very concise. Print 1-5 on a small card and get a 5 step off-camera flash guide. Maybe something to bundle with your DVDs?

October 01, 2008 7:22 AM  
Anonymous Anonymous said...

In the second photo description you say you...

"dialed in the shutter to set the ambient to a stop-and-a-half down"

Could you say a little bit more about that? How did you know what shutter speed would give a stop and half down? As the reference was the flash, and the flash doesn't care about shutter you never actually knew what the ambient exposure was, so how can you go a stop and half down from it? Am I being dim?

October 01, 2008 7:44 AM  
Blogger simonSE15 said...

sounds like Mr Hobby's got the hump answering all those f/stop/iso questions!

October 01, 2008 7:57 AM  
Blogger Photoplasia said...

I understand that setting in-cam white balance helps to visualize via the jpg preview on the LCD, but since you are shooting in RAW, isn't this an extraneous step?

October 01, 2008 8:01 AM  
Anonymous Dave said...

Hi Dave,
I've been following your blog for a while now and this is my first time commenting. I think its great that you have decided to move in this direction. You have coddled us far too long and its time for us take the next step. I can totally relate to the idea that the f/stops and shutter speeds are just immaterial. I own an A/C business and I always get asked what the blue gauge should read or what the red gauge should read. The answer is irrelevant because the conditions are never the same be it A/C or Photography. The answer will be different every day of the week because the conditions are different every day of the week. I think people get it for the most part and its just become a bad habit where the focus is on irrelevant f/stops and shutter speeds. I think you can provide the necessary nudge that will shift the focus back to where it belongs so that we can all move forward. I just have one question...what was the aperture on that photo of your friend:)
Dave in NJ

October 01, 2008 8:01 AM  
Blogger Jason Bell said...

Amen preacher! I just love this post.


October 01, 2008 8:05 AM  
Blogger Toby Fairchild said...

I think that this way of conveying lighting concepts is much more useful than rattling off a string of numbers. If the person receiving the information doesn't understand the general relationship between those elements then all the numbers in the world are quite simply useless. Although, those magic numbers seem to be all beginners (understandably) want to know. I face the same challenge with some of my private music students (I am a professional musician and photograph part time for a magazine). I try to stress the fact that although you may be able to define a group of notes played simultaneously as a D minor 7 chord, that information is useless until you take into consideration the chords that come before and after it and the RELATIONSHIP that they have with each other. The names and nomenclature are just tools, not answers. Anyway, I found this post to be right on the money.

October 01, 2008 8:57 AM  
Anonymous Thomas Goggans said...

Bravo David,
The first thing I did when I found your site (which is the single best site of its kind) was look around to discover the vocabulary used to describe what was being said. The terms and ways of talking about the same things vary, but it wasn't that hard to pick up the precise nomenclature. I have to be honest, though I have been shooting for 15 years, I never had any formal training at all, or even someone to learn from. So when I discovered Strobist there was a lot of the standard terminology that I wasn't familiar with; I understood the concepts, just not the verbiage. But it was clear that all I had to do was look around a bit, and presto! there was all the clarifying info I needed.
You always explain everything very clearly and simply. That's why Strobist is so great. So thanks and keep it up!

October 01, 2008 9:08 AM  
Blogger Jesse said...

Anonymous said...

In the second photo description you say you...

"dialed in the shutter to set the ambient to a stop-and-a-half down"

Could you say a little bit more about that? How did you know what shutter speed would give a stop and half down? As the reference was the flash, and the flash doesn't care about shutter you never actually knew what the ambient exposure was, so how can you go a stop and half down from it? Am I being dim?

He knew by using the camera's built-in light meter. If you have the camera in Manual mode, you'll see a meter along the bottom of your viewfinder that changes as you aim the lens at brighter/darker areas. Normally, you want that meter to be dead in the middle - "zeroed out" - for proper exposure of a given area. But he wanted 1.5 stops under "proper" exposure for a darker background to really contrast the subject. So he zeroed it out using the shutter speed dial (faster shutter speed = shorter exposure = darker; lower shutter speed = longer exposure = brighter), and then increased the shutter speed until the meter read just below "proper" exposure.

Once he's got the ambient light where he wants it (controlled by shutter speed), he can control the flash output either manually or by varying the aperture on the camera.

Hope that makes sense.

October 01, 2008 9:29 AM  
Blogger Mike said...

This post reminds me of my photography classes. A lot of people start taking down every single f-stop and setting that the professor mentions, and I'm like, dude what's the point? Next time the lighting conditions are going to be completely different, even if you shoot in the exact same spot. When I tell my fellow students that it's the ratios that matter not the actual settings, most of them don't get it. :(

Good post. I really like the short hand way of describing lighting and the direction that the blog is heading towards. Thanks David.

October 01, 2008 9:44 AM  
Blogger levi said...

I've had a few folks accuse me of not knowing what I'm doing because I can't remember power settings and f-stops for every shot I've made. I shall re-direct them here. Most don't seem to get that even the most subtle changes in ambient will change your outcome whilst working on location. Even if we did remember, we can't really set up the same shot, over and over again for many reasons..
Thanks David! And thanks METADATA, LOL.

October 01, 2008 10:53 AM  
Blogger MASilva said...

Great post David!

I would be really interested in learning a bit more about your process for "building" the shot, especially as another reader pointed out for those shots with several lights and no ambient. Do you take a reading (photo) with each light, or do you set all the lights up at one time and fine tune, or with no ambient do you have a good idea at the start so that you don't really need to do an ambient/fill flash reading?

Thanks so much!

October 01, 2008 11:07 AM  
Blogger The Stevens said...


Thanks so much for this! I'm more of a shoot from the hip photog and have been killing myself trying to get "uber-accurate" with my off camera skills.

It's like you gave me permission to go back to my roots and shoot from the hip again!

Thanks Dude! Keep it up!

October 01, 2008 11:55 AM  
Blogger christopherbautista said...

amen to this post DH

October 01, 2008 12:05 PM  
Anonymous Brandon D. said...

I understand that setting in-cam white balance helps to visualize via the jpg preview on the LCD, but since you are shooting in RAW, isn't this an extraneous step?

No, not quite. There's another school of thought on that. Imagine that you've done a photo shoot and that you've shot 300 images altogether. If you shot the whole thing on Daylight white balance in-camera, when you knew you needed to have shot it all on Tungsten white balance, then you'd have to "remember" to fix the white balance on up to 300 images.

Even at the post-processing stage, having to fix the white balance on all of your images, instead of getting it right (or very close) in-camera in the first place, can be very tedious.

Frankly, I think it ultimately saves time during the post-processing stage to get everything right in-camera that's possible. I mean, it only takes me 10 seconds at the max. to set the white balance in-camera.

Not only that, even when you shoot RAW and set white balance in-camera, what you see on the back of the LCD is comparable to a JPG of what the image will look like. Is it 100% accurate? No. But does it present a general idea of what the image will look like in your RAW editor? Yes. So for those who depend on the LCD for visual information, it makes sense to set the white balance in-camera so they have a feel for what they're doing during the shoot.

And so, just because shooting RAW allows you to set white balance during post-processing doesn't mean that you shouldn't do your best to get it right in-camera. It's just another school of thought. The thing I like about RAW is that it allows me to change my mind about white balance after I've made an educated guess in-camera.

October 01, 2008 1:36 PM  
Anonymous Rafael said...

Thanks to set me free! :)

It's in fact much easier to think of light this way than in absolute numbers.

Thanks again.

October 01, 2008 2:08 PM  
Blogger kim said...

great post, david! i think this is really going to help me understand the relationships better. i am sooo not into memorizing numbers :)

October 01, 2008 2:24 PM  
Blogger Mike Spivey said...

I raced dirt track stock cars for many years. I was considered somewhat of an expert at setting up chassis. I was always getting guy who wanted me to give them the "trick setup". I felt the exact same way you do when people want shutter speeds and f stops. I had a baseline, but I would never take the car on the track at the baseline. Our "ambient" was the amount of moisture in the dirt track. Like sunset shoots, our ambient was a rapidly moving target.

Great stuff, David. Loved the DVD.

October 01, 2008 2:45 PM  
Blogger Chris Werner said...

This is a great post! I'm a total beginner at this, but changing to this style of communication is not only *not* a hindrance, it's a huge plus. Yes, a plus from a beginner's perspective.

It cuts things down to the essence of the issue, and by doing so enables me to apply the concepts to other situations. That's true learning. Thanks!

October 01, 2008 3:28 PM  
Anonymous Nathanael Gassett said...

After reading a post like this, I can completely visualize a new wave of photographers coming up with some insane images. I am so grateful you've made this kind of information so easily attainable.
(WARNING: Personal Story junk below)
I actually just quit my barista job downtown to do photography full time *makes the sign of the cross* and I owe 99.8% of my lighting knowledge to you, sir. Strobist is like a college course in lighting, and you are quite the teacher.
Look forward to the next post, as always!


October 01, 2008 3:59 PM  
Anonymous Luis Vargas said...

David, Now That everyone has read this, I think that the lighting info on the pool it´s gonna change just a bit. hahah


October 01, 2008 4:09 PM  
Blogger Sergei Rodionov said...

Yup... All Hail David! ;)

I cant count how many conversations i had lately explaning to people why keeping EXIFs and talking in numbers is not important. For that matter - even keeping proper lighting diagramm with numbers, angles and distances and power settings.. I mean who cares.. As long as you know what was used and HOW - thats it. You can nail it any time you feel like reproducing look. Sure , one can run about and asking me for EXIFs of some portrait, but will the shoot same person with same skin, same makeup, same hair colour? Most likely - no. So why would they ever want these "in stone" numbers instead of understanding how and why certain light was used and poses taken..

Anyway.. Just ranting. As usual - you nailed problem far better than i am :)

Journalism background shows up.. ;)

Keep it up, man. And thank you. Would be so nice to talk ideas and not just "5.6f stop, 1/8 power.. blah"

October 01, 2008 4:31 PM  
Anonymous Jimster71 said...

I also thought you were starting to sound like Joe McNally, but I enjoy his blog too!

I like that concise shot description. The f-stop and shutter speed info is useless unless you can replicate the conditions that the image was shot in - very difficult when using ambient.

October 01, 2008 5:33 PM  
Anonymous Jeff said...

I just shot a wedding last week with a friend. I used to be all about the numbers (I still am, sort of) prior to shooting the wedding. But since everything was happening so fast for the group shots that we strobed, I was talking and thinking just like how you described without even knowing it. It really does help your workflow thinking in these terms.

October 01, 2008 5:50 PM  
Blogger David said...

Funny you guys should mention the Joe McNally thing. THe reason is (and to Joe's credit) he is talking to you the way pro photographers talk to each other.

He started out at full speed, and it was up to you to catch up. I started you out from Square One, and have tried to bring you along. (Those of you who are amateurs, at least -- the pros were already there.)

Essentially, I am raising the language level up a few notches from here on out, and making as post that I will refer to within future posts that will help.

The newbs get the info (via the link), and the vets do not get condescended to. And hopefully, we all learn to think in a more streamlined way.


October 01, 2008 6:42 PM  
Blogger gman said...

I think Zack Arias has eloquently stated the problem/solution with a few simple precepts. When I watched his workshop video I was stunned with how simple the rules really are and how they relate. To put the precepts in strobist parlance I'd classify them as lighting 101 (this is basically your exposure):

1. shutter controls your ambient exposure
2. aperture controls your subject exposure

and lighting 102 (this is about the quality of light and best use of resources):

1. flash power is used to refine your subject exposure vis-a-vis ratios between multiple flashes
2. flash to subject distance controls falloff/feathering of the light and depth of lighting plane primarily; secondarily controls subject exposure
3. ISO can be used to manipulate recycle time or have the effect of squeezing "more power" out of the same flash head

October 01, 2008 6:47 PM  
Anonymous Michael said...

In the Brooks DVD Dean Collins said about the settings, "it was f-good. f-as_its_always_been."

October 01, 2008 7:02 PM  
Anonymous Edgar aka fooddude said...

great post...this is exatly how I feel when talking about lighting. I just point to the scene on M mode,
adjust either SS, Ap, iso so the ambient/background is maybe 2-3 stops under on the exp-meter in the VF, then adjust the key flash first to get the flash lighting right, then adjust all other flashes relative to the key.

But..when you said that you adjust your Ap to control the flash light strength (in that table lamp shot) because its easier, isnt this incorrect? I mean that I thought that any adjustments on the camera (whether it be iso, Ap, SS), controls the ambient, and NOT the flash/strobe lighting. ??

Also, thanks for the tips on relativity on Key vs. Rim. I always wondered how many stops average do photogs usually use. (I ssume its 2-3.5 stops). I find in my experimentation that even a rim light of 2 stops less than key is still kinda overblown.

October 01, 2008 8:11 PM  
Anonymous Michael said...

To further add to why you should shoot with the proper WB in raw, some people shoot RAW+jpeg for fast turn around on the images. Proofs and such.

Now you can save that extra space on your card and use IJFR utility. It will instantly give you jpegs from your raw files. Any in-camera processing applied.

Check out Scott Kelby's blog guest entry at

October 01, 2008 9:53 PM  
Blogger brian said...

Super post, David. It's like going to Waffle House--20 words later you have the full order for a table of 4. I know a lot of the technical stuff now, and this is a great way to push it into practice.

October 01, 2008 11:12 PM  
Blogger Q Master said...

One question though!

If I have only SB600s how do I dial down the rim light two stops relative to the key ?

Is there a solution to that problem ?


October 01, 2008 11:19 PM  
Blogger Daniel Heywood said...

Edgar aka fooddude said...

...when you said that you adjust your Ap to control the flash light strength (in that table lamp shot) because its easier, isnt this incorrect? I mean that I thought that any adjustments on the camera (whether it be iso, Ap, SS), controls the ambient, and NOT the flash/strobe lighting. ??

Edgar: Opening up the aperture lets in more light, and closing the aperture lets in less light, whether that light is ambient or flash. So any light that affects the image, whether ambient or flash, will have either greater or lesser affect on the image when you change the aperture. Same with ISO.

You're spot on, though about shutter speed. So long as you're within the sync speed of your camera, it doesn't affect the effect of the flash, because the flash lasts for thousandths of a second. Since all the light that the flash puts out happens all at once and then is gone just as fast, a longer exposure doesn't allow any more of the light from the burst of flash to enter the lens.

October 01, 2008 11:37 PM  
Blogger Doug Holcomb said...

I like that your going to use that lingo now, I often find myself thinking too much of my aperture numbers and not enough on what I'm trying to accomplish!

One thing I don't really understand is the 1/4 CTO... does the 1/4 refer to a 1/4 stop??

October 02, 2008 12:28 AM  
Blogger said...

I dig the simplified approach. I'm teaching a photo masterclass soon, and will be introducing the ambient/flash concept from the start. Too often, new photographers worry about settings instead of feeding on their own creativity. Kudos!

October 02, 2008 4:18 AM  
Blogger Jerome Love said...

i have to say this post has probably made the most sense to me out of any other post on this site. i think that is with help from reading the rest of the site though. wow david, thank you for "breakin' it down" like this, i find myself looking through the site and many others with a whole new set of eyes. are we going to be talking like this throughout the seminar? my biggest struggle is "designing" the light, pre-visualizing it. i think with this technique of reverse engineering, i'm able to see so much more clearly what others are doing and manipulate my own images with ideas from what i want to do in my head and what i've seen.

October 02, 2008 5:23 AM  
Anonymous Jimster71 said...

@Q Master

Say you have the sb600 that is your main light running at 1/2 power. If you have your rim lights at the same distance from the subject as the main light, setting them at 1/8 power will be 2 stops below the main. Keeping them at the same distance from the subject is key here, otherwise you start playing with the inverse square law for the light power.

October 02, 2008 8:04 AM  
Anonymous Bill Rogers said...

Perfect! That's how it's done. Here's another example: Shot at ambient, plus an off-camera SB-800 thru an umbrella to light the subject.

October 02, 2008 9:36 AM  
Anonymous Phil Winterbourne said...

Conceptually this is how I work - as a TTL strobist I tend to use the exposure compensation, flash compensation, and flash ratio controls on my canon IR trigger.

I know this doesn't give me the same repeatability of full manual, but it does set all the exposure parameters as relative to the nominal "correct" exposure.

So I might look at a scene and dial in -1 stop of exposure and an extra stop of flash compensation (say to counder the shoot through).

This has always seemed much more intuative than dealing in numbers.

October 02, 2008 10:48 AM  
Blogger Ian said...

Oh how much easier it would be for you David, if everyone could just grasp this kind of explanation! Somehow I think that's wishful thinking.

After 20 years, sharing my space with another guy who's worked for 25, THIS is how we talk about lighting.

I just got asked by a model/wannabe"What F stops do you use?" SURE sign of a wannabe

October 02, 2008 1:57 PM  
Blogger jt said...

David, I really like the change. More recently I've just found all the numbers confusing (though it can be helpful if I have the exact same gear).
For the record, I'm on my 3rd year studying Greek, and this is way easier!

October 02, 2008 7:55 PM  
Anonymous MikeD said...

Stupid question, what was the flash settings of the Key light on Shadi? Is it the same as the ambient light or two stops down? I take it that the flash wasn't set just by lowering flash power eh? Thanks in advance.

October 02, 2008 10:45 PM  
Anonymous MikeD said...

DH, so let me get this straight,
1) Take a Auto photo to get the ambient light (ie 1/60,f2.8,800)
2) Then go to Manual and drop it 2 stops (1/125,f4,800)
3) Then just adjust the flash so that the histogram has a nice bell curve?
Is that it? Really?

October 02, 2008 11:27 PM  
Blogger Leon said...

I have only two exceptions where absolute f/stop and shutter speed mattter:

1. xsync speed for my rebel xt is 1/200 second, so I have to be aware of that as I set my ambient and have to keep an eye on it as I make subsequent adjustments.

2. I like shooting portraits at f/8, anything bigger and I have trouble keeping focus, especially when I'm shooting my kids and they are moving all over the place.

October 04, 2008 3:47 AM  
Blogger falcopics said...

Great post as always. Over the last year I have learned tons.

The absolute numbers don't matter because every scene is different, and tastes are different. What matters is understanding the technique, and figuring out how to apply it for the effect you want. For example I was shooting a group of portraits at a local park here in NH on a bridge that was in the shade, with the sunlight filtering from behind the subject in a way that created a fantastic hair light. So I metered off my nature provided hairlight because that was the brightest part of the scene, and dropped 1 and a half stops -- just because I like that look. I was using a main flash on a cheap tri-pod somewhere between 30 and 45 degrees from the subject at about a 16th (based on a test shot), with on camera fill flash stopped down 1 to 1 and a half stops based on past experience with the 580EX. The main flash gives the detail, and balances against the hairlight while the fill flash lifts the shadows created by the main flash. The only numbers I know, is the shutter speed was 1/200th because that is the synch on the Canon 5D, the ISO was set for something that would correspondingly give me an aperture with my desired depth of field. I think the main thing is just go out and try something, take a shot, and adjust one thing and see what is different. The more you experiment the more intuitive this becomes. The real beauty is how quickly you can set up, which in my example was important because I was working in 20 minute time slots while moving around the park.

October 06, 2008 12:43 PM  
Anonymous Anonymous said...

So one quick question about dropping ambient, should this be dropped using shutter speed or aperture. Or will this make a difference to what we are shooting. Say a person outside at dusk, in what way would we drop the ambient light down to give the nice evening lights? Do we get the ambient background first or the correct flash and aperture setting?

October 07, 2008 4:52 AM  
Anonymous Anonymous said...

You use the term gobo when you discussed controlling the spill from your umbrella. Normally the term flag is used for this use. A gobo is a cutout piece of metal used to project an image when placed in front of a light.

October 07, 2008 8:26 AM  
Blogger M said...

Great post, super helpful. Thanks!

October 07, 2008 12:02 PM  
Blogger Mike said...

Re: October 07, 2008 4:52 AM

You use the shutter speed to control amount of ambient.

October 07, 2008 1:21 PM  
Anonymous Anonymous said...

Some times it is helpful to know ISO & shutter speed due to the restrictions of max flash synch speed...sometimes we are 'up against a wall' so to speak with a max synch (like 1/200 sec for me). For daytime shots that forces the ISO down and the aperture up just to keep the shutter speed below the max synch speed, and flash power is often not enough to match the aperture you end up with (so underexposing ambient is no longer an option).

October 07, 2008 6:02 PM  
Blogger Nicola Zingarelli said...

Problem. My ambient light usually is the sky, in fact I'm talking about taking pictures of a fisherman in a boat. If I underespose it by two stops then my SB600 doesn't have enough power to lit the subject and I'm talking about a real close shot, maybe I'm one ft from him. What am I doing wrong?

October 08, 2008 9:17 AM  
Blogger Mike said...

This is what I would do, set camera on lowest ISO, use shutter priority mode at highest sync speed to find out an aperture for a properly exposed sky, use that shutter/aperture combo and build up the flash to work with that. Make sure your flash is in manual, and also since you are working close you shouldn't need that much power. Otherwise you can try the high-speed technique that DH describes else where on the site.

October 08, 2008 10:17 AM  
Anonymous Anonymous said...

There's something missing in all this excitement - the use of focus. If you just spin your knobs on your digital slr until it looks good on the tiny LCD screen, and the highlights don't blink, you are not considering the creative use of the resolving power of the lens you are using.

You do need to know about the relationship of ISO - f-stop - and shutter speed, in order to render something other than "good enough". Ask any pro.

October 09, 2008 3:38 PM  
Blogger David said...


Um, we are pretty much assuming you can figure out the focusing thing on your own . . .

October 09, 2008 7:04 PM  
Anonymous Anonymous said...


Um, we are pretty much assuming you can figure out the focusing thing on your own . . ."


Right. I get the premise that: "It's the relationship between the different light levels that is important."

All I was trying to get at is that you do need to think about your f-stop if you are going to select depth of field. The first photo has 5 steps - between two and three there might be a half-second intuition about how the f-stop will affect the look of the image - deep focus to wide open blurred background. That decision will be made for you, if you use auto to meter.

Sorry if I sounded like a jerk-face - I really do love your site and I think you have changed photography. I see it everywhere, especially in smaller newspapers, and community flyers, where you know they don't have the Vogue Magazine budget.

October 09, 2008 9:27 PM  
Blogger David said...


There are other ways to alter flash exposure without affecting DOF:

1) Move the flash
2) Change flash power
3) Alter the ISO and compensate w/shutter

More than one way to skin a cat...

October 10, 2008 12:16 AM  
Blogger Chris Cowell said...

Hah, managed it at last!

Thanks for this - totally (well, mostly) understand the process now :)

October 16, 2008 3:23 AM  
Anonymous miguel said...

i totally agree with the sentiment. when someone asks me what settings were used, i always tell them - even if i told you, it won't help you because the likelihood that the same exact settings will be valid when they're shooting is practically nil.

it's almost like the people overly concerned with specific DoF measurements - I just couldn't get through to this one guy when i was trying to explain a "shorthand" version of it (because it's just plain impractical to do the calculations every single time), but I've noticed the obsession with specifics are generally limited to a certain demographic. but i won't mention it since i don't want to offend anyone.

October 21, 2008 11:23 AM  
Blogger focusfinder said...

I agree about the shorthand. The numbers don't really matter all that much.

Example at:

Peter Bryenton

October 28, 2008 3:15 PM  
Blogger Lola said...

Ok, Im really sorry for asking a dumb question here, but I am new to this site and still trying to get to grips with the ambient/flash balance. I completely understand when you refer to finding the ambient exposure (either by taking a shot on auto or zeroing out at manual) and then stopping down or up, but what Im don't get is when you refer to then overexposing or underexposing the flash. Im assuming we are all using our flash guns on manual here, so we can fire them with the PWs, so what is the reference point for stopping down or up the flash?
Can someone please just clarify this for me?

January 11, 2009 4:26 AM  
Anonymous Clara said...

@Lola, you can't really under or overexpose the flash. What I gather is that you gauge from the ambient exposure what power to put the flash on, if you're not killing the ambient.

If you're killing the ambient you use a desirable power in order to adequately light the subject without drowning it in light.

I am very new at this myself so I just chimp and adjust... David, correct me if I'm wrong or not explaining this very well.

Thanks for the post. People easily get caught up in the technical details with photography, it's easy to forget how to be creative and to experiment rather than stick religiously to numbers and f stops.

February 06, 2009 4:13 PM  
Blogger Richard Cooper said...

Always good information.

Would also be helpful if you state whether your are shooting RAW or JPEG.

September 12, 2011 1:43 PM  
Blogger Roberto Santiago Rodriguez said...

Makes a lot of sense actually; the specifics of Shutter and F stop would not be the same each time so why worry what those settings were a the time. It is as stated so eloquently all about rate between light and shadows and effect intended.

September 09, 2014 7:34 AM  

Post a Comment

<< Home